Conveying apparatus



Jan. 26, 1943. WQ M. scHWEicKART ETAL 2,309,418

l CONVEYING APPARATUS Filed Aug. l, 1940 2 Sheets-Sheet l ATToRNr-:YJ

Jan. 26, 1 943. w, M. scvHwElcKAR-l; ETAL 2,399,418

CONVEYING APPARATUS Filed Aug. l, 1940 2 Sheets-Sheet 2 ATTORNEYPatented Jan. 26, 1943 TENT orties Euclid, Ohio, assignors to PocahontasFuel Company Incorporated, New York, N. Y., a corporation of VirginiavApplication August 1, 1940, Serial No. .l49,348

2 Claims.

This invention relates to improvements in apparatus for collecting andconveying coal and the like, and is particularly directed to a systemoperable beneath an accumulation of coal for transferring the coal froma substantial area to the inlet of a conveyor system. It is particularlySuitable for operation in a coal bin to provide a constant anddependable supply of coal to a conveyor preferably of the worm or screwtype, which feeds the coal to a furnace.

In installations of this type, proper feeding of the coal is highlyimportant for the purpose of assuring proper burner operation, foreconomy in driving the feed screws, and to avoid the jamming of the feedwhich has heretofore been a prolic source of trouble in apparatus ofthis type.

The object of the invention is to overcome these difculties and providea uniform feed to the main conveyor regardless of the depth andcondition of the coal. A more specic object is to Supply a device forcollecting the coal from a substantial area that will avoid the bridgingof the coal and the jamming or stoppage of the feed, and the presentinvention is an improvement of applicants prior device shown in PatentNo. 2,233,085.

Other objects and advantages of the invention will appear from thefollowing description considered in connection with the accompanyingdrawings, in which,

Fig. 1 is a vertical longitudinal section of a collector unit;

Fig. 2 is a perspective View of one of the collector blade sections orpick-up flights shown in Fig. 1;

Fig. 3 is an end View of the pick-up flight of Fig. 2;

Fig. 4 is a side elevation of the of Fig. 2;

Fig. 5 is a fragmental bottom View of the pickup ight of Fig. 2, takenas indicated by the arrows 9-9 of Fig. 4; and Fig. 6 is a perspectiveView of the pick-up flight of Fig. 2 from another angle and after thepickup iiight has been rotated about its axis from the position shown inFig. 2.

The coal collector unit is adapted to be mounted in a coal bin and has arotating collector arm differentially rotating and swinging to gatherand draw the coal to a feed pocket at the end of the coal feed tube, asillustrated in Fig. 1 and in the apparatus of applicants Patent2,233,085 on which this present case is an improvement. The bincollector unit is driven from the main coal pick-up flight feed screw 2lrotating in the coal feed tube 22 and having a suitable drive connectionwith a vertical rotating drive sleeve 33 carrying a planetary drive forthe collector arm. In the form i1- lustrated, the tubular end of feedscrew 2| is coupled to pick-up screw section 23 in appropriate mannerand the end of the coal feed tube 22 is adjustably clamped to thecollector by the integral mounting collar 56.

The pick-up screw 23 has its screw Iiight Welded uponan extension of thecore or shaft portion 6i) of the coal screw 2l. The coal and pick-upscrews 2 I 23 are preferably provided with a series of projections 6Ialong the edge of the screw blade as particularly described in theapplication of William M. Schweickart, Serial No. 355,564, led May 16,1940, these projections greatly facilitating' the handling and conveyingof wet or moist fine coal.

The outer end of pick-up screw 23 is bolted to one end of a shaft 62 onthe other end of which is mounted the bevel gear 28. Roller bearings 63and 64 rotatably support shaft 62 and absorb any thrusts to which it issubjected. Bearing 63 consists of an inner bearing cone 65 mounted onthe shaft 62 and against a shoulder thereon, an outer bearing cone 66mounted in the cylindrical opening in the extension 26 of the basehousing 2l, and suitable rollers positioned between the bearing cones.The position of outer bearing cone 66 is adjustable by the bearingtakeup ring 6l, this ring being secured to the housing 21 by a set screw68 threaded in the extension 26. Surrounding the shaft 62 and betweenthe shaft and the take-up ring 6l is a suitable seal 69 for keeping coaland dust out of the bearings and for preventing the oil or other gearand bear' ing lubricant from leaking out of the housing 2'1.

Bearing 64 consists of an inner bearing cone 'l0 mounted on the stud 30,an outer bearing cone 1| mounted on the bevel gear 28 and in a suitablepocket therein, and suitable rollers positioned between the bearingcones. The hub sleeve 3| in which th stud 30 is mounted is an interiorsleeve formation of base housing 27 extending downwardly from the top ofthe housing, and is preferably connected near its lower end to the bodyof the base housing by one or more spokes or ribs 72. Base housing 21 issecured to the base 21a. which rests on the oor of the bin and has anextension formed with a collar 56 for clamping on to the end of the coalfeed tube 22. y

Bevel gear 28 meshes with and drives the bevel gear 32 which is mountedat the lowerend of the tubular shaft or sleeve 33. The-sleeve 33 isrotatably supported by the bushings 59 in the base housing 21 andextends vertically out of the lower housing 21 and up into the upperhousing 4|. With the direction of rotation of the coal and pick-upscrews 2|, 23 as shown by the arrows AA, the direction of rotation ofthe sleeve 33 is that shown by the arrows BB.

Within the sleeve 33 is positioned the cover shaft or disc-supportingstandard 35a, the lower end Of which abuts against the bottom of thebase 21a. The upper end of the standard 35a is welded to a cover, discor hat 53a, which is preferably a steel stamping.

The lower housing 21 is provided with an oil hole and plug 13 and thenormal level of the oil 14 in the housing is the lower edge of the Oilhole. The diameter of the cover shaft 35a, is a little less than theinside diameter of sleeve 33 throughout the length of the shaft 35o`except for a region above and below the normal oil level, in whichregion the diameter of the cover shaft 35a is substantially less thanthe inside diameter of the sleeve 33, thereby providing an annularchamber 15 between the sleeve 33 and shaft 35a. An aperture 16 isprovided in the sleeve 33 to form a passageway from the chamber 15 tothe outside of the sleeve. An aperture 11 is provided in the hub sleeve3| of the lower housing 21 to form a passageway from the outside ofsleeve 33 to the main body of oil contained within the base housing 21.As a result of this construction relief is provided for the Oilsubjected to the pumping action of the parts within the base housing 21.This pumping action tends to force oil upwardly between the shaft35a'and sleeve 33 during the operation of the collector, and the reliefconsists in having the oil first rise in the chamber 15 to the level ofthe passageway 16 and thereupon pass through the passageways 'I8 and 11back to the main body Of oil. There is thus no loss of Oil from thelower housing due to any inherent pumping action of the parts.

The blade Or paddle 51a is shown as formed of two suitable shaped fiatplates 18, 19 positioned face to face and suitably secured to the hub58, as Vby a plurality of rivets 38. A single plate of suitablethickness may be employed if desired. The leading edge of the paddle 51apreferably has applied to it an abrasive resisting material. The hub 58is secured to drive sleeve 33 by a plurality of set screws 8|, the innerends of which are preferably pin-like cylinders of reduced diametertting into suitable apertures in the drive sleeve 33. This constructionnot only secures the hub 58 to the Adrive sleeve but also enables thehub to support the upper housing 4|,

The upper housing 4| has an interior sleeve formation or hub 48extending upwardly from the bottom of the housing and is preferablyconnected near its upper end to the body of the upper housing by one ormore spokes or ribs 82. Housing sleeve 40 surrounds the drive sleeve 33and is rotatably mounted thereon, suitable bushings or bearings 42, 83being provided respectively at the bottom and top Vof the housing sleeve48. The bottom face of the lower bushing 42 engages the top face of thehub 58 and the upper face of this lower bushing abuts against a shoulderin the hub 48, so that the housing 4| is supported upon hub 58 throughthe lower bushing 42.

Within the upper housing 4| is the bevel gearing 38, 31, the gear 36being secured to drive sleeve 33 near its top and the gear 31 having itsaxis horizontal and below gear 38. Gear 31 is rotatably supported onstud 39 by the ball bearing 39 and is mounted upon a connecting sleeve43 at the inner end thereof. This sleeve is rotatably supported within atubular exten'- sion 84 of the upper housing 4| by means of two bushings44, 44a.. The sleeve 43 projects outside extension 84, where it issuitably connected, as by the pin 85, to the Outrigger shaft 48. Theinner end of this shaft is positioned in sleeve 43 and extends inwardlya substantial distance. Mounted on the outer end of Outrigger shaft 48and secured thereto are the pick-up units or coal impelling elements 8S,81 and 88, the parts together forming the coal collector arm 45a. Withthe drive sleeve 33 rotating in the direction shown by the arrows BB,the direction of rotation of the Outrigger shaft 46 and of the coalcollector arm 45a is that shown by the arrows CC.

'I'he pick-up units 81 and 88 are the end units at the inner and outerends, respectively, of the collector arm, while the units 8B are theintermediate units, there being a substantial number of suchintermediate units, for example, seven for a 2li-inch collector unit andten for a thirty-inch collector unit.

Referring now to Figs. 2 to 6, inclusive, showing an individualintermediate pick-up unit 86 unmounted upon the Outrigger shaft, theunit comprises a tubular hub 89 having integral therewith two blades,interrupted flights or paddies 99, 9|. These blades are substantiallydiammetrically opposed about the axis of the unit (see Fig. 3), arelongitudinally displaced along the axis of the unit (see Figs. 2, 4 and6), and are in planes inclined with respect to the axis cf the unit sothat coal is advanced longitudinally along the axis of the unit as theunit rotates about its axis The blades 99, 9| being similar information, a detailed description of one suffices.

The blade 98 subtends approximately a right angie at the axis of theunit (see Fig. 3) and 1s thinner at and near the outer edge than at thehub so that the edge is relatively sharp and knifelilre (see Figs. 2, 4and 5) and the Outer edge of the blade is serrated or notched to provide saw teeth 92 therealong facing in the general direction of rotationof the unit. These teeth 92 are relatively coarse, that is, relativelyfew in number and relatively long radially, and the teeth are relativelythin throughout their radial length.

The hubs 89 of all the pick-up units 88, 81 and 88 have interlocks, suchas tongues 93 and recesses 94, the end pick-up units 81 and 88 aresecured to the Outrigger shaft 48 by the bolts 95, 98 respectively, andthe blades on the end pickup units 81 and 88 are similar to those forthe intermediate pick-up units 86. Thus the individual pick-up unitstogether form a series of separate helically inclined blades on theOutrigger shaft 48. with these blades moving with the outrigger shaft 43as it rotates about its axis to feed coal inwardly toward the verticalaxis of the collector (i. e., the axis of drive sleeve 33), and withthese blades moving with the Outrigger shaft 4G as it rotates about suchvertical axis to advance the blades into a fresh supply of coal.

As a result of the above construction for the pick-up units, thecollector is particularly eiective to collect coal and convey it to thecoal vconveyor 2|, 22, especially when the coal is ne (such as coalslack) and wet. The thin sharp outer edges on the blades cut into thewall of coal ahead of the collector arm 45a so that the collector armcontinues to advance around the vertical axis of the collector (i. e.,the axis of drive sleeve 33) and feed coal even when the collector armencounters tightly packed coal, such as wet or damp slack. The teeth 92along the outer edges of the blades agitate the coal engaged by theblades and dislodge obstructions therein, such as coarse (i. e.,pea-sized) particles of coal embedded in the slack, tending to hinderthe advance of the collector arm 45a, and cause such particles to moveout of the path of the collector arm so that the collector arm continuesto advance and feed coal even when it encounters obstructions in thecoal. The sharp edges and thin teeth also serve to prevent overloadingof the collector unit. Thus, the rotation of the collector arm 65a aboutits own axis tends to pack the coal beneath the collector arm, and thistends to produce an upward thrust upon the collector arm. When the levelof the coal in the bin becomes low so that the weight of the coal abovethe collector arm is insufficient to counteract this upward thrust, thisupward thrust must be borne by the collector itself. In such case theload on the collector substantially increases and the outrigger shaft 45is subjected to severe strain-in some cases causing breakage of theOutrigger shaft. In preventing this, the sharp edges and teeth on theblades of the pick-up units described cut into the coal tending to packbeneath the collector arm instead of being supported by such coal,thereby reducing some of the upward thrust on the collector arm, and theteeth, being thin at their bases as well as at their tops, are unable tostabilize the coarse particles in such coal with the result that thecoal collector arm does not tend to climb and ride up over suchparticles, thereby also reducing some of the upward thrust on the coalcollector` arm.

Thus, as a result of the above construction for the blades of thepick-up units, these units insure a continuous feed of ne wet coalwithout injury to the collector unit. As an example, these pick-up unitshave been especially effective in collectors handling fine bituminouscoal on the order of 1/8 and 1A inch slack and containing some coarsepea-sized particles and having a moisture content around 8% and over.

As an example of a pick-up unit embodying the above features, thefollowing details are given for the pick-up unit 86 shown in Figs. 2-6inclusive:

A. Inside diameter of hub 89 -inches li-2 B. Outside diameter of hub 89do 118 C. Offset of centers for outer edge of blades 99, 9| and forbases of teeth 92 inches its D. Radius to outer edge of blades 90, 9|

inches 1% E. Radius to bases-of teeth 92 do l F. Angle subtended byblades 90, 9| neglecting the corner-eliminating face 91 degrees G. Anglesubtended by outer edge of blade degrees-- H. Angular distance betweenfront faces of teeth 92 degrees 221/2 I. Angle between front-l edge 93of blade 90 and line through axis of unit perpendicular to rear face 99of blade 99 degrees-- J. Length of unnotched outer edge of blade betweenadjacent teeth 92 inches 1-3.; K. Overall axial length of pick-up unit86 inches 23% L. Axial length of tongue 93 do M. Angle of working faceof blades 90, 9| with respect to plane transverse to axis of pick-upunit (this working face being a plane surface with the radius |90 fromthe axis of the pickup unit to the rear end of the outer edge of theblade lying within such plane surface) degrees N. Distance axially alonghub 89 between its innermost edge and the nearest .point on the workingface of blade 9i] inches 1 O. Thickness of blades 99, 9| at outer edgeinches-- gli P. Thickness of blades 9U, 9| at hub 89 inches 1/4 Thepick-up units of the foregoing proportions are especially suitable forcollecting and feeding coal to pick up and coal screws 2|, Z3 having anoutside diameter of 25/8 (including projections 6| each having a heightof 3% and a shaft diameter of 1%", with coal tube 22 having an insideldiameter of 3, with the pitch of pick-up screw 23 being 1v1/2 and withthe pitch of coal screw 2| being 21A".

We claim:

1. In a coal collector arm rotating around a horizontal axis andswinging around a vertical axis, a series of pickup flights along saidarm comprising hub portions and spaced blade portions with each bladesubtending approximately a right angle at the horizontal axis of the armand tapered from relative thickness at the hub to sharpness at the outeredge and notched at the sharp outer edge to provide coarse saw teethfacing in the direction of rotation and of the swinging movement of thearm when viewed from above.

2. Collector apparatus as set forth in claim 1 in which each tooth ofthe pickup blades subwim tends an arc of about 20 and has a length ofunnotched outer edge trailing the point of the tooth.

WILLIAM M. SCHWEICKART. FRED G. JULYAN.

